As Belle exited a gate at the San Diego International Airport on Friday, her tail started to wag.

The 3-year-old yellow Labrador, fresh off a deployment in Afghanistan, spotted a familiar face in the crowd — her partner in combat, Camp Pendleton Marine Sgt. Sam Wettstein.

Passers-by in the crowded terminal paused to watch Belle dart into his outstretched arms and leap up to lick his grinning face.

She was finally back with her best friend.

Belle is one of the growing number of military dogs that have been adopted by their former handlers or civilians in recent years, as the Iraq War ended and the U.S. presence in Afghanistan winds down.

Though often overlooked by the public, trained dogs have a long history with the armed forces. They traditionally served as guards and messengers, and they have played a key role in combat zones starting in World War II.

Marine Sgt. Sam Wettstein (left) plays Belle in the terminal area after reuniting with her at Lindberg Field on Friday in San Diego, California. Belle, a labrador who specialized in explosives detection, retired from duty and is being adopted by Wettstein who served with her in Afghanistan. — Eduardo Contreras

Marine Sgt. Sam Wettstein (left) plays Belle in the terminal area after reuniting with her at Lindberg Field on Friday in San Diego, California. Belle, a labrador who specialized in explosives detection, retired from duty and is being adopted by Wettstein who served with her in Afghanistan.
— Eduardo Contreras

Today, several hundred military or private-contract dogs are deployed around the world for war- or other security-related purposes. They belong to the Defense Department or, like Belle, are owned by a nongovernmental business and hired to work with the military.

Their most common duties are searching for explosives or narcotics; Belle specialized in detecting roadside bombs and the like.

Each dog saves 150 to 200 lives during their deployments, according to the American Humane Association in Washington, D.C., which works with other groups to find homes for such canines upon their retirement.

In past decades, retired dogs were typically discharged wherever they were located; the military or contract companies often did not pay to transport them home. It can cost thousand of dollars for vaccinations, paperwork and airfare — fees that hopeful owners are often unable to pay.

Last year, Mission K9 Rescue was officially formed to help fill some of these financial gaps. The group has teamed up with the American Humane Association to bring home numerous dogs that served overseas, including Belle.

These nonprofit organizations took to Capitol Hill last week to advocate for better care of retired military dogs, including greater funding and more coordinated adoption programs between the armed forces and civilian groups.

“They are still veterans, just with four legs and fur,” said Robin Ganzert, president and CEO of the American Humane Association. “On both sides of the leash, the dog and the handler, we want to make sure they are taken care of.”

Belle is the 14th military dog that has found a retirement home this year thanks to Mission K9 Rescue, which works with other partners.

“Seeing that bond they have, it makes it all worth it,” said K9 Rescue President Kristen Murer as she watched Belle skip around her at the airport.

Wettstein, 23, is originally from Wisconsin and now living in San Clemente. He and Belle were paired during training camp about a year ago, after the Marine underwent a series of personality tests that looked at his traits, his hobbies and even his favorite movies.

“We connected immediately,” Wettstein said, smiling at the memory. They are both goofy and active, he added.